1. Field of the Invention
One or more embodiments of the present invention relate to a nonwoven fabric and, for example, relate to a nonwoven fabric which is used in a membrane of a test tool using immunochromatography.
2. Description of Related Art
There are strong demands of a test tool which can easily and rapidly execute an extracorporeal diagnosis with high accuracy by a non expert of a clinical test according to enhancement of home healthcare or community healthcare in recent years. For example, a dry test tool (biosensor) using an immunoassay method such as immunochromatography can quantitatively or qualitatively and extremely easily analyze a test substance in a test solution, without preparation of a reagent.
The test tool described above is generally configured with a sheet-shaped porous material (membrane) in which the test solution is moved, a base sheet which holds the sheet-shaped porous material, and a reagent carried in a part of the porous material. The test substance can be analyzed with a simple operation of applying a solution including the test substance to a predetermined location of the porous material. Such a test is required to be performed faster and more accurately.
Below-described Patent Document 1 discloses a laminated nonwoven fabric in which two types of nanofibers having different fiber diameters are laminated, as the membrane used in such a test tool. That is, a surface area of the laminated nonwoven fabric can be secured with the nonwoven fabric having a small fiber diameter, and a movement speed of the test solution is improved with the nonwoven fabric having a large fiber diameter.
Patent Document 1 is Pamphlet of International Publication No. 2014/013635, and Patent Document 2 is JP-A-2013-78708.